#!/Library/Frameworks/Python.framework/Versions/3.5/bin/python3

s = input()

if 'RRR' in s:
    print('3')
elif 'RR' in s:
    print('2')
elif 'R' in s:
    print('1')
else:
    print('0') s = input() s input() input if 'RRR' in s:
    print('3')
elif 'RR' in s:
    print('2')
elif 'R' in s:
    print('1')
else:
    print('0') 'RRR' in s 'RRR' s print('3') print '3' elif 'RR' in s:
    print('2') 'RR' in s 'RR' s print('2') print '2' elif 'R' in s:
    print('1') 'R' in s 'R' s print('1') print '1' print('0') print '0' s = input() input() s
#!/Library/Frameworks/Python.framework/Versions/3.5/bin/python3

s = input()

if 'RRR' in s:
    print('3')
elif 'RR' in s:
    print('2')
elif 'R' in s:
    print('1')
else:
    print('0')
